Clear channel assessment (CCA) levels within wireless communications

ABSTRACT

A wireless communication device is configured to perform clear channel assessment (CCA) using one or more CCA levels that are selected based on various criteria. The device receives or detects one or more packets on the communication medium, and the device then processes those one or more packets to determine status of one or more channels within one or more frequency bands using the one or more CCA levels. These CCA levels may be selected based on one or more parameters, and different CCA levels may be used at different times, for different channels, etc. Also, different CCA levels may be used to determine the status of different channels, different portions of the frequency spectrum, etc. When at least one channel is determined as being clear and available for usage, the device is configured to support communications with one or more other devices via one or more channels.

CROSS REFERENCE TO RELATED PATENTS/PATENT APPLICATIONS ProvisionalPriority Claims

The present U.S. Utility Patent Application claims priority pursuant to35 U.S.C. §119(e) to U.S. Provisional Application No. 61/773,743,entitled “Clear channel assessment (CCA) levels within single user,multiple user, multiple access, and/or MIMO wireless communications,”filed Mar. 6, 2013; and U.S. Provisional Application No. 61/936,137,entitled “Clear channel assessment (CCA) levels within wirelesscommunications,” filed Feb. 5, 2014, both of which are herebyincorporated herein by reference in their entirety and made part of thepresent U.S. Utility Patent Application for all purposes.

BACKGROUND

1. Technical Field

The present disclosure relates generally to communication systems; and,more particularly, to performing clear channel assessment (CCA) withinsingle user, multiple user, multiple access, and/or MIMO wirelesscommunications.

2. Description of Related Art

Communication systems support wireless and wire lined communicationsbetween wireless and/or wire lined communication devices. The systemscan range from national and/or international cellular telephone systems,to the Internet, to point-to-point in-home wireless networks and canoperate in accordance with one or more communication standards. Forexample, wireless communication systems may operate in accordance withone or more standards including, but not limited to, IEEE 802.11x (wherex may be various extensions such as a, b, n, g, etc.), Bluetooth,advanced mobile phone services (AMPS), digital AMPS, global system formobile communications (GSM), etc., and/or variations thereof.

In some instances, wireless communication is made between a transmitter(TX) and receiver (RX) using single-input-single-output (SISO)communication. Another type of wireless communication issingle-input-multiple-output (SIMO) in which a single TX processes datainto RF signals that are transmitted to a RX that includes two or moreantennae and two or more RX paths.

Yet an alternative type of wireless communication ismultiple-input-single-output (MISO) in which a TX includes two or moretransmission paths that each respectively converts a correspondingportion of baseband signals into RF signals, which are transmitted viacorresponding antennae to a RX. Another type of wireless communicationis multiple-input-multiple-output (MIMO) in which a TX and RX eachrespectively includes multiple paths such that a TX parallel processesdata using a spatial and time encoding function to produce two or morestreams of data and a RX receives the multiple RF signals via multipleRX paths that recapture the streams of data utilizing a spatial and timedecoding function.

Clear channel assessment (CCA) is a process performed by a wirelesscommunication device to determine whether or not a transmission may bemade on a wireless communication channel. Current practices ofperforming CCA can result in low and inefficient usage of the wirelesscommunication channel. There continues to be much room for improvementin performing CCA to improve spatial spectral efficiency within wirelesscommunications.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a diagram illustrating one or more embodiments of a wirelesscommunication system.

FIG. 2 is a diagram illustrating an embodiment of a number of wirelesscommunication devices, some operative as smart meter stations (SMSTAs).

FIG. 3A is a diagram illustrating an example of communication betweenwireless communication devices.

FIG. 3B is a diagram illustrating an example of operation of one or morewireless communication devices.

FIG. 3C is a diagram illustrating another example of operation of one ormore wireless communication devices.

FIG. 3D is a diagram illustrating another example of operation of one ormore wireless communication devices.

FIG. 4 is a diagram illustrating an example of a frequency bandpartitioned into a number of channels.

FIG. 5 is a diagram illustrating an example of different frequency bandspartitioned into different numbers of channels.

FIG. 6 is a diagram illustrating an example of clear channel assessment(CCA) analysis as may be performed within a processor of a wirelesscommunication device.

FIG. 7A is a diagram illustrating an embodiment of a method forexecution by one or more wireless communication devices.

FIG. 7B is a diagram illustrating another embodiment of a method forexecution by one or more wireless communication devices.

FIG. 8A is a diagram illustrating another embodiment of a method forexecution by one or more wireless communication devices.

FIG. 8B is a diagram illustrating another embodiment of a method forexecution by one or more wireless communication devices.

DETAILED DESCRIPTION

FIG. 1 is a diagram illustrating one or more embodiments of a wirelesscommunication system 100. The wireless communication system 100 includesbase stations and/or access points 112-116, wireless communicationdevices 118-132 (e.g., devices that include wireless stations (STAs)and/or stand-alone wireless stations), smart meter stations (SMSTAs) 190and 191, and a network hardware component 134. The wirelesscommunication devices 118-132 may be laptop computers, or tablets, 118and 126, personal digital assistants 120 and 130, personal computers 124and 132 and/or cellular telephones 122 and 128. The details of anembodiment of such wireless communication devices are described ingreater detail with reference to FIG. 2.

The base stations (BSs) or access points (APs) 112-116 are operablycoupled to the network hardware 134 via local area network connections136, 138, and 140. The network hardware 134, which may be a router,switch, bridge, modem, system controller, etc., provides a wide areanetwork connection 142 for the communication system 100. Each of thebase stations or access points 112-116 has an associated antenna orantenna array to communicate with the wireless communication devices inits area. Typically, the wireless communication devices register with aparticular base station or access point 112-116 to receive services fromthe communication system 100. For direct connections (i.e.,point-to-point communications), wireless communication devicescommunicate directly via an allocated channel.

Any of the various wireless communication devices (WDEVs) 118-132 andBSs or APs 112-116 may include a processor and a communication interfaceto support communications with any other of the wireless communicationdevices 118-132 and BSs or APs 112-116.

In an example of operation, a communication interface implemented withinone of the devices (e.g., any one of the WDEVs 118-132 and BSs or APs112-116) is configured to receive one or more packets and supportcommunications with one or more other devices (e.g., any other of theWDEVs 118-132 and BSs or APs 112-116). A processor implemented withinthe device (e.g., any one of the WDEVs 118-132 and BSs or APs 112-116)is configured to process the one or more received packets to determinestatus of one or more channels. The one or more channels may beimplemented within one or more predetermined frequency bands. Theprocessor uses one or more clear channel assessment (CCA) levels todetermine status of the one or more channels. These CCA levels areselected based on any one or more of various criteria including a numberof channels within the one or more channels, one or more bandwidths ofthose one or more channels, etc. Based on the determined status of theone or more channels, the processor is configured to select at least oneof those channels for use in supporting communications with one or moreother devices. The processor is also configured selectively to directwhen the communication interface supports those communications based onthe determined status of one or more channels.

In performing clear channel assessment (CCA), if a wirelesscommunication device can or does receive, detect, or ‘hear’ a signalabove a given level (e.g., a given CCA level), then the wirelesscommunication device generally operates to defer access to thecommunication medium (e.g., air) and not access that channel, at leastfor some time. Alternatively, if a wireless communication device doesnot receive, detect, or ‘hear’ a signal above a given level (e.g., if itis below that level), then the wireless communication device can accessthe communication medium (e.g., air) and can access at least one channelto make a transmission. Generally, such operations determine if achannel is clear or not clear.

FIG. 2 is a diagram illustrating an embodiment 200 of a number ofwireless communication devices, some operative as smart meter stations(SMSTAs). The SMSTA are implemented in various locations in anenvironment including a building or structure. Some wirelesscommunication devices may be implemented to support communicationsassociated with monitoring and/or sensing of any of a variety ofdifferent conditions, parameters, etc. Such wireless communicationdevices provide such sensed/monitored information to one or more otherwireless communication devices (e.g., from the SMSTAs to an AP).

A SMSTA has communication functionality similar to a wireless station(STA) and is also operative to perform communication of monitoringand/or sensing related information. In certain applications, suchdevices may operate only very rarely. For example, when compared to theperiods of time in which such a device is in power savings mode (e.g., asleep mode, a reduced functionality operational mode a lowered poweroperational mode, etc.), the operational periods of time may beminiscule in comparison (e.g., only a few percentage of the periods oftime in which the device is in such a power savings mode).

An SMSTA may awaken from such a power savings mode only to performcertain operations. For example, such a device may awaken from such apower savings mode to perform sensing and/or measurement of one or moreparameters, conditions, constraints, etc. During such an operationalperiod (e.g., in which the device is not in a power savings mode), thedevice may transmit such information to another wireless communicationdevice (e.g., an access point (AP), another SMSTA, a wireless station(STA), or such an SMSTA or STA operating as an AP, etc.).

In an SMSTA environment, multiple respective wireless communicationdevices (e.g., SMSTAs) can be implemented to forward monitoring and/orsensing related information to one particular wireless communicationdevice that operates as a manager, coordinator, etc. such as may beimplemented by an access point (AP) or a wireless station (STA)operating as an AP. Such SMSTAs may be implemented to perform any of anumber of data forwarding, monitoring and/or sensing operations. Forexample, in the context of a building or structure, there may be anumber of services that are provided to that building or structure,including natural gas service, electrical service, television service,Internet service, etc. Alternatively, different respective monitorsand/or sensors may be implemented throughout the environment to performmonitoring and/or sensing related to parameters not specifically relatedto services. As some examples, motion detection, door ajar detection,temperature measurement (and/or other atmospheric and/or environmentalmeasurements), etc. may be performed by different respective monitorsand/or sensors implemented in various locations and for variouspurposes. Communications from SMSTAs may be very important and yetperformed quite infrequently. When communications from SMSTAs are notreceived by the manager, coordinator, etc. wireless communicationdevice, one or more systems that use such monitoring and/or sensinginformation suffer performance degradation.

Any one of the devices within such an embodiment 200 may be implementedto perform processing the one or more received packets to determinestatus of one or more channels and to use one or more CCA levels todetermine status of the one or more channels. Based on the determinedstatus of the one or more channels, the device may then select at leastone of those channels for use in supporting communications with one ormore other devices and also then selectively direct when to supportthose communications based on the determined status of one or morechannels.

FIG. 3A is a diagram illustrating an example 301 of communicationbetween wireless communication devices. A wireless communication device310 (e.g., which may be any one of devices 118-132 as with reference toFIG. 1) is in communication with another wireless communication device390 via a transmission medium. The wireless communication device 310includes a communication interface 320 to perform transmitting andreceiving of one or more frames (e.g., using a transmitter 322 and areceiver 324). The wireless communication device 310 also includes aprocessor 330, and an associated memory 340, to execute variousoperations including generating and/or interpreting one or more frames,packets, signals, etc. transmitted to wireless communication device 390and/or received from the wireless communication device 390 and/orwireless communication device 391. The wireless communication devices310 and 390-391 may be implemented using one or more integrated circuitsin accordance with any desired configuration or combination orcomponents, modules, etc. within one or more integrated circuits. Also,the wireless communication devices 310, 390, and 391 may each includemore than one antenna for transmitting and receiving of one or moreframes (e.g., WDEV 310 may include one or more antennae, WDEV 390 mayinclude m antennae, and WDEV 391 may include n antennae).

The communication interface 320 is configured to receive one or morepackets and to support communications with one or more other wirelesscommunication devices (e.g., devices 390-391). The processor 330 isconfigured to process the one or more packets to determine status of oneor more channels within a predetermined frequency band using one or moreclear channel assessment (CCA) levels that are selected based on anumber of channels of the one or more channels and one or morebandwidths of the one or more channels. The processor 330 is alsoconfigured to select at least one channel of the one or more channelsbased on the determined status of the one or more channels. Theprocessor 330 is also selectively configured to direct when thecommunication interface 320 supports the communications with the one ormore other wireless communication devices (e.g., devices 390-391) on theselected at least one channel based on the determined status of the oneor more channels.

The processor 330 within the device may also be configured to processthe one or more packets to determine certain characteristics of thoseone or more packets, and then select the one or more CCA levels based onthose characteristics. For example, the processor 330 may process theone or more packets to determine the number of channels within the oneor more channels, the one or more bandwidths of those one or morechannels, a rate at which the one or more packets is received, one ormore modulation coding sets (MCSs) of the one or more packets, etc. andthen select the one or more CCA levels based on any one or more of thosedetermine characteristics. In addition, when two or more channels areimplemented within one or more predetermined frequency bands, theprocessor 330 may select a CCA level based on the particular channel viawhich the one or more packets are received. For example, when a packetis received via a first channel, the processor 330 may use a first CCAlevel to determine status of that first channel. Alternatively, when apacket is received via a second channel, the processor 330 may use asecond CCA level to determine status of the second channel. The variouschannels may be implemented within different frequency bands ordifferent frequency sub-bands that may have different sizes. Forexample, a first channel may be located within a first frequencysub-band that is of a different size (e.g., wider or narrower) this thana second channel that is located within the second frequency sub-band.In addition, a given channel may be formed using two or more channels,such as in a bonded channel configuration in which two adjacent channelsare combined to form the bonded channel. Alternatively, two or morenon-adjacent channels may be combined to form another channel.

FIG. 3B is a diagram illustrating an example 302 of operation of one ormore wireless communication devices. Device 310 is configured to performCCA to determine when access to the communication medium may be made sothat it may make one or more transmissions to one or more other devices,such as devices 390-391. In this diagram, device 310 detects or receivesno packets from devices 390-391. There may be times during which device310 detects no energy and receives no packets, and device 310 may thensupport communications using any desired channel.

FIG. 3C is a diagram illustrating another example 303 of operation ofone or more wireless communication devices. In this diagram, device 310detects or receives first packets from device 390 and may also detectand receive second packets from device 391. The device 310 processes thefirst packets received from device 390 using one or more CCA levels thatare selected based on a number of channels and the number of bandwidthsof those channels via which the first packets are received. Generally,the partitioning of one or more frequency bands into one or morechannels may be described as channelization. A given frequency band mayhave different channelizations at different times. By determining achannel and bandwidth of the channel via which a packet is received, thedevice 310 may determine the channelization of the predeterminedfrequency band. For example, by firstly determining such information ofthe received packet, the device may secondly determine the overallchannelization of the predetermined frequency band. Then, the device 310may select the one or more CCA levels based on that information.

FIG. 3D is a diagram illustrating another example 304 of operation ofone or more wireless communication devices. In this diagram, device 310selects at least one of the one or more channels based on the determinedstatus of the one or more channels and selectively supportscommunications with device 390 by transmitting third packets to device390. Device 310 may also be configured to select at least one of the oneor more channels based on the determined status of the one or morechannels and selectively supports communications with device 391 bytransmitting fourth packets to device 391. In some instances, the sameat least one channel may be used to support communications with bothdevices 390-391. Also, in some instances, device 310 may transmit thesame packets to both devices 390-391. Generally speaking, when status ofat least one of the one or more communication channels is deemedacceptable, such as when any packet or signal is detected received thathas an energy, signal, or power level (or other measurand or parameter)that is below a corresponding CCA level, then device 310 may select thatat least one channel to support communications with at least one of thedevices 390-391.

FIG. 4 is a diagram illustrating an example 400 of a frequency bandpartitioned into a number of channels. A predetermined frequency band(PFB) may be partitioned into different numbers of channels of differentsizes at different times based on different channelizations. At the topof the diagram, a first channelization (CHN 1) shows the PFB asincluding a number ‘x’ channels each having a common size or bandwidth.Below, a second channelization (CHN 2) shows the PFB as including anumber ‘y’ channels each having a common size or bandwidth that arerelatively wider than the ‘x’ channels of CHN 1.

At the bottom of diagram, an n-th channelization (CHN n) shows the PFBas including a number ‘z’ channels. These channels are ofnon-uniform/different sizes or bandwidths. In addition, at least one ofthe channels, channel 4 (CH4), is shown as being formed from channels 2and 3 in a bonded channel configuration such that channel 4 has the sizeor bandwidth of channels 2 and 3 combined.

As can be seen, the PFB can be partitioned into one or more channels.Then, one or more CCA levels may be selected based on the particularchannelization that is detected and determined. In one example, achannelization may include one singular channel that spans the entirePFB. In another example, the PFB may be partitioned into 2 channels thattogether span the predetermined frequency band. Generally speaking, aPFB may be partitioned into any desired number of channels of anydesired sizes or bandwidths, and the channel widths need not be ofuniform size. Also, more than one PFB may be partitioned into the one ormore channels, and such two or more PFBs may be adjacently located ornon-adjacent to one another such that they are located in differentportions of the frequency spectrum. In one example, such one or morePFBs may be included within frequency bands below 1 GHz excluding the TVWhite Space bands, with a transmission range up to 1 km and a minimumdata rate of at least 100 Kb/s.

Generally, different channelizations may be used based on any one ormore criteria including one or more communication protocols being used,one or more remote and/or local operating conditions of various deviceswithin a system, etc. A device may switch between differentchannelizations adaptively based on any such criteria. When a packet isreceived via a given channel, the receiving device may be configured toassess the one or more channels on which the packet has been transmittedand then will be able to determine the channelization of the one or morePFBs. Based on such determine information related to the number ofchannels and bandwidths of those channels, the device may then beconfigured to select one or more CCA levels to determine status of thoseone or more channels. Different CCA levels may be selected depending onwhich channel the packet is received, the bandwidth of that channel, andthe overall channelization of the PFB. Within any given channelization,certain of the channels may have particular designations, such asprimary, secondary, and/or other designations.

FIG. 5 is a diagram illustrating an example 500 of different frequencybands partitioned into different numbers of channels. This diagram showsdifferent respective predetermined frequency bands that are partitioneddifferently with respect to different channelizations. In this diagram,some of the frequency bands occupy similar portions of the frequencyspectrum as others, yet different frequency bands may be located suchthat they occupy entirely non-overlapping portions of the frequencyspectrum.

In a first channelization (CHa), two adjacent channels of similarbandwidth are included within a first predetermined frequency band(PFB1). The entirety of the first predetermined frequency band may be 2MHz, and each of the two adjacent channels therein may be of 1 MHzbandwidth. One of the channels may be designated as a primary channel,and the other may be designated as a secondary channel.

In a second channelization (CHb), four adjacent channels of similarbandwidth are included within a second predetermined frequency band(PFB2) that also occupies a common portion of the frequency spectrumoccupied by the first predetermined frequency band (PFB1). The entiretyof the second predetermined frequency band may be 4 MHz, and each of thefour channels therein may be of 1 MHz bandwidth. In addition to oralternatively, two adjacent channels (Cha1 and Cha2) of similarbandwidth (e.g., 2 MHz) are included within a second predeterminedfrequency band (PFB2). In this alternative example, the two adjacentchannels (Cha1 and Cha2) may each be viewed as formed using two of thefour channels (e.g., Cha1 formed using CH1 and CH2, and Cha2 formedusing CH3 and CH4) such as in a bonded channel configuration. In onepossible implementation, one of the channels may be designated as aprimary channel, and the other may be designated as a secondary channel.

In a third channelization (CHc), four adjacent channels of similarbandwidth are included within a third predetermined frequency band(PFB3) that occupies those portions of the frequency spectrum occupiedby the first and second predetermined frequency bands (PFB1 and PFB2)and additional frequency spectra. The entirety of the thirdpredetermined frequency band may be 8 MHz, and each of the four adjacentchannels therein may be of 2 MHz bandwidth. One of the channels may bedesignated as a primary channel, and the other may be designated as asecondary channel.

In a fourth channelization (CHd), eight adjacent channels of similarbandwidth are included within a fourth predetermined frequency band(PFB4) that occupies those portions of the frequency spectrum occupiedby the first, second, and third predetermined frequency bands (PFB1,PFB2, and PFB3) and additional frequency spectra. The entirety of thefourth predetermined frequency band may be 16 MHz, and each of the fouradjacent channels therein may be of 2 MHz bandwidth. One of the channelsmay be designated as a primary channel, and the other may be designatedas a secondary channel.

FIG. 6 is a diagram illustrating an example 600 of clear channelassessment (CCA) analysis as may be performed within a processor of awireless communication device. This diagram shows an example ofprocessor 330 performing CCA analysis. Processor 330 is configured toprocess a received packet or signal to determine whether or not theenergy, signal, or power level (or other measurand and/or parameter) ofthe received packet or signal is above one or more CCA levels. Thisexample shows two separate CCA levels to which a given measurand and/orparameter may be compared. In other implementations, one or three ormore CCA levels may be used. When the measurand and/or parameter isgreater than a given CCA level, the processor 330 generates a busyindication based on that CCA level. Alternatively, when the measurandand/or parameter is less than a given CCA level, the processor 330generates a clear indication based on that CCA level. If the measurandand/or parameter is exactly the same as a given CCA level, the processor330 may be configured to generate either a clear or busy indicationdepending on a desired implementation.

At the bottom left of the diagram, a singular CCA level (CCA0) is shownfor use across a wide range of the frequency spectrum. The processor 330is configured to selective the same CCA level (CCA0) for use to processpackets received via any of the channels one through x (CH1-CHx).

At the bottom right of the diagram, multiple CCA levels are shown foruse across a various channels within the frequency spectrum. Forexample, the processor 330 is configured to select a first CCA level(CCA1) for use to process packets received via a first channel (CH1).The processor 330 is also configured to select a second CCA level (CCA2)for use to process packets received via a second channel (CH2).Generally, the processor 330 is configured to select differentrespective CCA levels for use to process packets received via differentrespective channels.

The processor 330 may be configured to adapt its operation among asingular CCA level operational modes and one or more multiple CCA leveloperational modes. For example, based on one or more remote and/or localoperating conditions, the processor 330 may operate using a selected CCAlevel operational mode over others. Then, based on a change of any ofthe one or more remote and/or local operating conditions, the processor330 may operate using a different selected CCA level operational mode.In one example of operation, a frequency band is partitioned into twoseparate portions such that one or more first channels are includedwithin a first portion and one or more second channels are includedwithin the second portion, and the processor 330 is configured to use afirst CCA level to process packets received via the one or more firstchannels and a second CCA level to process packets received via the oneor more second channels.

An energy detect (ED) level may be used to perform clear channelassessment (CCA). The ED level may be set at −62 dBm for 20 MHzwaveforms. The ED level may be scaled with respect to bandwidth (e.g.,increase as bandwidth increases). Note that some embodiments mayconsider the number of available channels, while others may not takeinto account the number of available channels. For example, in a 2.4 GHzimplementation, a basic services set (BSS) can move to one of threechannels if higher than −62 dBm interference exists in a given channel(e.g., this level is 20 dB higher than that used for preambledetection). However, such operation may be in a different frequencyband.

Such operation may also take into account the total available bandwidth.For example, some implementations in the USA used three 8 MHz channels.Some implementations in Korea use three 2 MHz channels. These aresimilar to the channelization of 2.4 GHz three 20 MHz channels. Forexample, if the level is above this, it is assumed that the channel isbusy; if such a signal is detected at all times, then the wirelesscommunication device can move to another channel. Therefore, −62 dBm maybe used for 8 MHz in the USA and 2 MHz in Korea and similarly in othercountries. However, this approach may not adequately compensate for theimproved propagation and it also creates different levels for the samebandwidth in different countries.

Such operation may also take into account interference with Zigbee (IEEE802.15.4) based on certain bandwidth considerations. For example, Zigbeeuses 5 MHz channelization in 2.4 GHz and 2 MHz channelization in 900MHz. As such, a 20 MHz WiFi signal interferes with 4 Zigbee channels in2.4 GHz and an 8 MHz WiFi signal interferes with 4 Zigbee signals in 900MHz. A wireless communication device configured to use the same level of−62 dBm for 20 MHz in 2.4 and 8 MHz in 900 may sometimes lead to thesame protection of 4 Zigbee channels but at greater distance in 900 MHz.

Also, a wireless communication device may be configured to considerinterference with Zigbee (IEEE 802.15.4) based on certain rateconsiderations. For example, Zigbee's bit rate is 40 kbps in 900 MHzwith specification sensitivity: −92 dBm and 250 kbps in 2.4 GHz withspecification sensitivity −85 dBm. The 7 dB improved sensitivity at 900MHz allows for deferral at a 7 dB higher power and use −62+7=−55 dBm/20MHz, or equivalently −62 dBm/4 MHz. This gives a bandwidth ratio of 5equivalent to 7 dB.

A wireless communication device can be configured to perform CCAdifferently for primary and secondary channels. For example, a wirelesscommunication device can be configured to perform preamble detectionusing a first CCA level or a primary channel level. A level of −82 dBmmay be used for 20 MHz, and this will provide a 20 dB difference from−62 dBm that is used for energy detect (ED) level). A wirelesscommunication device can be configured to ignore packets detected below−82 dBm.

A similar 20 dB difference between ED level and preamble detection levelmay be employed for different channelizations. For example, −82 dBm maybe used for 4 MHz channelization, −85 dBm may be used for 2 MHzchannelization, −91 dBm may be used for 1 MHz channelization, −79 dBmmay be used for 8 MHz channelization, and −76 dBm may be used for 16 MHzchannelization. As such, a wireless communication device can beconfigured to ignore packets detected those levels.

Similarly to the discussion above for CCA levels for primary channeldetection, a wireless communication device may be configured to use adetection level on a secondary 20 MHz signal that is the midpointbetween the detection level on the primary channel and the ED detectionlevel. For example, considering the ED level for 2 MHz channels is −65dBm and the primary channel detection level for 2 MHz channel is −85dBm, a wireless communication device may be configured to performdetection on a secondary 2 MHz channel of 1 MHz or 2 MHz waveform usingat a level −75 dBm.

With respect to the selectivity of one or more CCA levels based on oneor more criteria, note that selectivity of one or more CCA levels may bemade based on category or type of wireless communication device. Forexample, a high elevation access point (AP) (e.g., an AP implemented ina relatively high elevation compared to other wireless communicationdevices in the system) may present uniquely challenging situations dueto topology issues compounded by the improved sensitivity andpropagation of signals less than 1 GHz frequencies. As an example, anytransmission by such a high elevation AP causes interference to wirelesscommunication devices within overlapping basic services sets (OBSSs). Assuch, some wireless communication devices may be configured to relax CCAlevels only for hose such APs (e.g., such as High Elevation AP) by 10dB. That means that the 2 MHz primary channel level may be set at −75dBm which is the secondary level for low elevation devices. Similarly,the secondary level is set at −65 dBm which is the ED level for lowelevation devices and the Ed level is set at −55 dBm.

As another example of selectivity of one or more CCA levels may be madebased on category or type of wireless communication device, specialrules may be used to select CCA levels for low power and/or batteryoperated wireless communication devices. As an example, certain lowpower battery operated devices (e.g., sensors or smart meter stations(SMSTAs)) may be configured to transmit around 0 dBm. As such, thesedevices create relatively less interference than others. For example, ifa low power device hears a high power device transmitting at 15 dBm at acertain level (e.g., −70 dBm), then that device will hear the low powerdevice at a much lower level (−85 dBm for a 0 dBm transmit power). Then,a wireless communication device may be configured to relax the CCA rulesfor low power battery operated devices transmitting at or around 0 dBmby 10 dB as well.

As another example of selectivity of one or more CCA levels may be madebased on category or type of wireless communication device, specialrules may be used to select CCA levels for wireless communicationdevices having a certain type of analog front end (AFE). For example,wireless communication devices configured to with a 1 MHz AFE areconfigured to operate in a 1 MHz BSS and may use a 1 MHz front endfilter to improve rejection of transmissions in the adjacent channels. Awireless communication device that uses a 1 MHz front end filter candisable the ability to decode the 2 MHz signal field (SIG). This issomewhat similar to 4 MHz, 8 MHz, and 16 MHz transmissions that use aduplicated 2 MHz SIG field design. In such an instance, these waveformsdo not use a duplicated 1 MHz SIG field. In order to decode a 2 MHz SIGfield, a device may be configured to decode a 2 MHz signal.

A wireless communication device can include a 1 MHz front end filter andthen will not be able to decode the 2 MHz SIG field using a CCA levelfor a detected 2 MHz signal. Such a wireless communication device may beconfigured to use a CCA level of 91 dBm for 1 MHz. If a wirelesscommunication device with a 1 MHz front-end filter detects a 2 MHzsignal but cannot decode the 2 MHz SIG field, the wireless communicationdevice employs a CCA level of −91 dBm. Such a wireless communicationdevice may be configured to avoid large asymmetry between the CCA rulesof 2 MHz devices that can always decode the SIG field of 1 MHz devices.

It is noted that such specific levels presented herein are exemplary,and different respective specific values may alternatively be employedin various instances. For example, the principle of relaxation ofrespective clear channel assessment (CCA) values employed for a HighElevation AP may be effectuated using a different specific value than arelaxation of specifically 10 dB (e.g., 5 dB relaxation, 8 dBrelaxation, etc. or generally X dB relaxation [where X is a selectednumber] may be employed). Similarly, the principle of relaxation ofrespective clear channel assessment (CCA) values employed for a lowpower and/or battery operated devices may be effectuated using adifferent specific value that a relaxation of specifically transmittingat or around 0 dBm by 10 dB (e.g., 5 dB relaxation, 8 dB relaxation,etc. or generally X dB relaxation [where X is a selected number] may beemployed).

FIG. 7A is a diagram illustrating an embodiment of a method 701 forexecution by one or more wireless communication devices. The method 701begins by receiving one or more packets (e.g., via a communicationinterface of a wireless communication device) (block 710). Then, themethod 701 continues by processing the one or more packets to determinestatus of one or more channels within a predetermined frequency bandusing one or more clear channel assessment (CCA) levels that areselected based on a number of channels of the one or more channels andone or more bandwidths of the one or more channels (block 720).

The method 701 then operates by selecting at least one channel of theone or more channels based on the determined status of the one or morechannels (block 730). The method 701 continues by supportingcommunications with one or more other wireless communication devicesusing the selected at least one channel during one or more times basedon the determined status of the one or more channels (block 740).

FIG. 7B is a diagram illustrating another embodiment of a method 702 forexecution by one or more wireless communication devices. The method 702begins by receiving one or more packets (e.g., via a communicationinterface of a wireless communication device) (block 711).

The method 702 continues by processing the one or more packets todetermine one or more characteristics thereof (block 713). Examples ofsome characteristics of the one or more packets may include any one of anumber of channels via which the one or more packets have been received,one or more bandwidths of the one or more channels, one or more ratesvia which the one or more packets are received (such as a data rate,symbol rate, transmission rate, etc.), one or more modulation codingsets (MCSs) of the one or more packets, and/or any other desiredcharacteristic.

The method 700 then operates by selecting the one or more CCA levelsbased on the one or more characteristics (block 715). In one example,the one or more CCA levels are selected based on the number of channelsof the one or more channels, the one or more bandwidths of the one ormore channels, and the rate at which the one or more packets isreceived.

Then, the method 702 continues by processing the one or more packets todetermine status of one or more channels within a predeterminedfrequency band using one or more CCA levels that are selected based on anumber of channels of the one or more channels and one or morebandwidths of the one or more channels (block 721).

The method 702 then operates by selecting at least one channel of theone or more channels based on the determined status of the one or morechannels (block 731). The method 702 continues by supportingcommunications with one or more other wireless communication devicesusing the selected at least one channel during one or more times basedon the determined status of the one or more channels (block 741).

FIG. 8A is a diagram illustrating another embodiment of a method 801 forexecution by one or more wireless communication devices. The method 801operates by selecting first one or more channels based on determinedstatus of at least one of the first one or more channels (block 810).The status of these first one or more channels is determined using firstone or more CCA levels. Then, the method 801 continues by supportingcommunications using those selected first one or more channels (block820). The operations of the blocks 810 and 820 may be viewed as beingperformed at or during a first time.

The method 801 may optionally perform a number of analogous operationsas performed in the blocks 810 and 820 with respect to selecting andsupporting communications using second selected one or more channels,and/or third selected one or more channels, etc.

The method 801 then continues by selecting n-th one or more channelsbased on determined status of at least one of the n-th one or morechannels (block 830). The status of these n-th one or more channels isdetermined using n-th one or more CCA levels. Then, the method 801continues by supporting communications using those selected n-th one ormore channels (block 840). The operations of the blocks 830 and 840 maybe viewed as being performed at or during an n-th time (which may be asecond time, a third time, a fourth time, etc.).

FIG. 8B is a diagram illustrating another embodiment of a method 802 forexecution by one or more wireless communication devices. The method 802operates by receiving one or more packets (block 811). The method 802continues by processing the received one or more packets to determinestatus of one or more channels using one or more clear channelassessment (CCA) levels (block 821).

If the status of at least one of the one or more channels comparesfavorably to at least one criterion indicating that the channel is clear(block 831), then the method 802 continues by selecting at least one ofthe one or more channels indicated as clear based on the determinedstatus (block 841). Then, the method 802 operates by supportingcommunications with one or more other wireless communication devicesusing the selected at least one channel (block 851).

Alternatively, if the status of at least one of the one or more channelsfails to compare favorably to at least one criterion indicating that thechannel is clear (block 831), then the method 802 may continue byreceiving an additional one or more packets (block 811). Generally,determination is made whether or not one or more channels is availablefor use in supporting communications. When no channels are determined asbeing clear are available, then the method 802 operates by notsupporting any communications. In such a situation, a number ofoperations may be performed including performing a timeout, a backup, orsome other operation to wait a period of time, which may be apredetermined period of time or and adaptively determined period oftime, after which the method 802 may perform additional operations todetermine status of the one or more channels and their capability tosupport communications.

It is noted that the various operations and functions described withinvarious methods herein may be performed within a wireless communicationdevice (e.g., such as by the processor 330, communication interface 320,and memory 340 as described with reference to FIG. 3A) and/or othercomponents therein. Generally, a communication interface and processorin a wireless communication device can perform such operations.

Examples of some components may include one of more baseband processingmodules, one or more media access control (MAC) layer components, one ormore physical layer (PHY) components, and/or other components, etc. Forexample, such a processor can perform baseband processing operations andcan operate in conjunction with a radio, analog front end (AFE), etc.The processor can generate such signals, frames, etc. as describedherein as well as perform various operations described herein and/ortheir respective equivalents.

In some embodiments, such a baseband processing module and/or aprocessing module (which may be implemented in the same device orseparate devices) can perform such processing to generate signals fortransmission to another wireless communication device using any numberof radios and antennae. In some embodiments, such processing isperformed cooperatively by a processor in a first device and anotherprocessor within a second device. In other embodiments, such processingis performed wholly by a processor within one device.

As may be used herein, the terms “substantially” and “approximately”provides an industry-accepted tolerance for its corresponding termand/or relativity between items. Such an industry-accepted toleranceranges from less than one percent to fifty percent and corresponds to,but is not limited to, component values, integrated circuit processvariations, temperature variations, rise and fall times, and/or thermalnoise. Such relativity between items ranges from a difference of a fewpercent to magnitude differences. As may also be used herein, theterm(s) “configured to”, “operably coupled to”, “coupled to”, and/or“coupling” includes direct coupling between items and/or indirectcoupling between items via an intervening item (e.g., an item includes,but is not limited to, a component, an element, a circuit, and/or amodule) where, for an example of indirect coupling, the intervening itemdoes not modify the information of a signal but may adjust its currentlevel, voltage level, and/or power level. As may further be used herein,inferred coupling (i.e., where one element is coupled to another elementby inference) includes direct and indirect coupling between two items inthe same manner as “coupled to”. As may even further be used herein, theterm “configured to”, “operable to”, “coupled to”, or “operably coupledto” indicates that an item includes one or more of power connections,input(s), output(s), etc., to perform, when activated, one or more itscorresponding functions and may further include inferred coupling to oneor more other items. As may still further be used herein, the term“associated with”, includes direct and/or indirect coupling of separateitems and/or one item being embedded within another item.

As may be used herein, the term “compares favorably”, indicates that acomparison between two or more items, signals, etc., provides a desiredrelationship. For example, when the desired relationship is that signal1 has a greater magnitude than signal 2, a favorable comparison may beachieved when the magnitude of signal 1 is greater than that of signal 2or when the magnitude of signal 2 is less than that of signal 1.

As may also be used herein, the terms “processing module”, “processingcircuit”, “processor”, and/or “processing unit” may be a singleprocessing device or a plurality of processing devices. Such aprocessing device may be a microprocessor, micro-controller, digitalsignal processor, microcomputer, central processing unit, fieldprogrammable gate array, programmable logic device, state machine, logiccircuitry, analog circuitry, digital circuitry, and/or any device thatmanipulates signals (analog and/or digital) based on hard coding of thecircuitry and/or operational instructions. The processing module,module, processing circuit, and/or processing unit may be, or furtherinclude, memory and/or an integrated memory element, which may be asingle memory device, a plurality of memory devices, and/or embeddedcircuitry of another processing module, module, processing circuit,and/or processing unit. Such a memory device may be a read-only memory,random access memory, volatile memory, non-volatile memory, staticmemory, dynamic memory, flash memory, cache memory, and/or any devicethat stores digital information. Note that if the processing module,module, processing circuit, and/or processing unit includes more thanone processing device, the processing devices may be centrally located(e.g., directly coupled together via a wired and/or wireless busstructure) or may be distributedly located (e.g., cloud computing viaindirect coupling via a local area network and/or a wide area network).Further note that if the processing module, module, processing circuit,and/or processing unit implements one or more of its functions via astate machine, analog circuitry, digital circuitry, and/or logiccircuitry, the memory and/or memory element storing the correspondingoperational instructions may be embedded within, or external to, thecircuitry comprising the state machine, analog circuitry, digitalcircuitry, and/or logic circuitry. Still further note that, the memoryelement may store, and the processing module, module, processingcircuit, and/or processing unit executes, hard coded and/or operationalinstructions corresponding to at least some of the steps and/orfunctions illustrated in one or more of the Figures. Such a memorydevice or memory element can be included in an article of manufacture.

One or more embodiments of an invention have been described above withthe aid of method steps illustrating the performance of specifiedfunctions and relationships thereof. The boundaries and sequence ofthese functional building blocks and method steps have been arbitrarilydefined herein for convenience of description. Alternate boundaries andsequences can be defined so long as the specified functions andrelationships are appropriately performed. Any such alternate boundariesor sequences are thus within the scope and spirit of the claims.Further, the boundaries of these functional building blocks have beenarbitrarily defined for convenience of description. Alternate boundariescould be defined as long as the certain significant functions areappropriately performed. Similarly, flow diagram blocks may also havebeen arbitrarily defined herein to illustrate certain significantfunctionality. To the extent used, the flow diagram block boundaries andsequence could have been defined otherwise and still perform the certainsignificant functionality. Such alternate definitions of both functionalbuilding blocks and flow diagram blocks and sequences are thus withinthe scope and spirit of the claimed invention. One of average skill inthe art will also recognize that the functional building blocks, andother illustrative blocks, modules and components herein, can beimplemented as illustrated or by discrete components, applicationspecific integrated circuits, processors executing appropriate softwareand the like or any combination thereof.

The one or more embodiments are used herein to illustrate one or moreaspects, one or more features, one or more concepts, and/or one or moreexamples of the invention. A physical embodiment of an apparatus, anarticle of manufacture, a machine, and/or of a process may include oneor more of the aspects, features, concepts, examples, etc. describedwith reference to one or more of the embodiments discussed herein.Further, from figure to figure, the embodiments may incorporate the sameor similarly named functions, steps, modules, etc. that may use the sameor different reference numbers and, as such, the functions, steps,modules, etc. may be the same or similar functions, steps, modules, etc.or different ones.

Unless specifically stated to the contra, signals to, from, and/orbetween elements in a figure of any of the figures presented herein maybe analog or digital, continuous time or discrete time, and single-endedor differential. For instance, if a signal path is shown as asingle-ended path, it also represents a differential signal path.Similarly, if a signal path is shown as a differential path, it alsorepresents a single-ended signal path. While one or more particulararchitectures are described herein, other architectures can likewise beimplemented that use one or more data buses not expressly shown, directconnectivity between elements, and/or indirect coupling between otherelements as recognized by one of average skill in the art.

The term “module” is used in the description of one or more of theembodiments. A module includes a processing module, a processor, afunctional block, hardware, and/or memory that stores operationalinstructions for performing one or more functions as may be describedherein. Note that, if the module is implemented via hardware, thehardware may operate independently and/or in conjunction with softwareand/or firmware. As also used herein, a module may contain one or moresub-modules, each of which may be one or more modules.

While particular combinations of various functions and features of theone or more embodiments have been expressly described herein, othercombinations of these features and functions are likewise possible. Thepresent disclosure of an invention is not limited by the particularexamples disclosed herein and expressly incorporates these othercombinations.

What is claimed is:
 1. A wireless communication device comprising: acommunication interface; and a processor, the processor and thecommunication configured to: receive one or more packets; supportcommunications with one or more other wireless communication devices;process the one or more packets to determine status of one or morechannels within a predetermined frequency band using one or more clearchannel assessment (CCA) levels that are selected based on a number ofchannels of the one or more channels and one or more bandwidths of theone or more channels; select at least one channel of the one or morechannels based on the determined status of the one or more channels; andselectively direct when the communication interface supports thecommunications with the one or more other wireless communication deviceson the at least one channel based on the determined status of the one ormore channels; receive a packet via a first two or more channels withinthe predetermined frequency band or a second two or more channels withinthe predetermined frequency; process the packet to determine the statusof the first two or more channels using a first CCA level when thepacket is received via the first two or more channels; and process thepacket to determine the status of the second two or more channels usinga second CCA level when the packet is received via the second two ormore channels.
 2. The wireless communication device of claim 1, whereinthe at least one of the processor or the communication interface isfurther configured to: process the one or more packets to determine arate at which the one or more packets is received; and select the one ormore CCA levels based on the number of channels of the one or morechannels, the one or more bandwidths of the one or more channels, andthe rate at which the one or more packets is received.
 3. The wirelesscommunication device of claim 1, wherein the processor and thecommunication interface are further configured to: receive the packetvia a first channel within the predetermined frequency band or a secondchannel within the predetermined frequency band; process the packet todetermine the status of the first channel using a first CCA level whenthe packet is received via the first channel; and process the packet todetermine the status of the second channel using a second CCA level whenthe packet is received via the second channel.
 4. The wirelesscommunication device of claim 3, wherein: the first channel is locatedwithin a first frequency sub-band of the predetermined frequency band;and the second channel is located within a second frequency sub-band ofthe predetermined frequency band that is wider or narrower than thefirst frequency sub-band.
 5. The wireless communication device of claim1, wherein the processor and the communication interface are furtherconfigured to: support the communications with the one or more otherwireless communication devices using a first channel at or during afirst time; and support the communications with the one or more otherwireless communication devices using a second channel at or during asecond time.
 6. The wireless communication device of claim 1, wherein:the first two or more channels are located within a first frequencysub-band of the predetermined frequency band; and the second two or morechannels are located within a second frequency sub-band of thepredetermined frequency band that is wider or narrower than the firstfrequency sub-band.
 7. The wireless communication device of claim 1,wherein: at least one of the first two or more channels or the secondtwo or more channels span the predetermined frequency band.
 8. Thewireless communication device of claim 1 further comprising: a wirelessstation (STA) or a smart meter station (SMSTA), wherein the one or moreother wireless communication devices includes another STA, anotherSMSTA, or an access point (AP).
 9. A wireless communication devicecomprising: a communication interface; and a processor, the processorand the communication configured to: receive a packet; supportcommunications with one or more other wireless communication devices;process the packet to determine a rate at which the packet is received,one or more channels within a predetermined frequency band, and one ormore bandwidths of the one or more channels within the predeterminedfrequency band via which the packet is received; determine status of theone or more channels using one or more clear channel assessment (CCA)levels that are selected from a plurality of CCAs based on the rate, theone or more channels, and the one or more bandwidths; selectively directwhen the communication interface supports the communications with one ormore other wireless communication devices based on the determined statusof the one or more channels; receive the packet via a first two or morechannels within the predetermined frequency band or a second two or morechannels within the predetermined frequency; process the packet todetermine the status of the first two or more channels using a first CCAlevel when the packet is received via the first two or more channels;and process the packet to determine the status of the second two or morechannels using a second CCA level when the packet is received via thesecond two or more channels.
 10. The wireless communication device ofclaim 9, wherein the processor and the communication interface arefurther configured to: support the communications with the one or moreother wireless communication devices using a first channel at or duringa first time; and support the communications with the one or more otherwireless communication devices using a second channel at or during asecond time.
 11. The wireless communication device of claim 9, wherein:the first two or more channels are located within a first frequencysub-band of the predetermined frequency band; and the second two or morechannels are located within a second frequency sub-band of thepredetermined frequency band that is wider or narrower than the firstfrequency sub-band.
 12. The wireless communication device of claim 9,wherein, wherein at least one of the first two or more channels or thesecond two or more channels span the predetermined frequency band. 13.The wireless communication device of claim 9 further comprising: awireless station (STA) or a smart meter station (SMSTA), wherein the oneor more other wireless communication devices includes another STA,another SMSTA, or an access point (AP).
 14. A method for execution by awireless communication device, the method comprising: via acommunication interface of the wireless communication device, receivingone or more packets; processing the one or more packets to determinestatus of one or more channels within a predetermined frequency bandusing one or more clear channel assessment (CCA) levels that are basedon a number of channels of the one or more channels and one or morebandwidths of the one or more channels; selecting at least one channelof the one or more channels based on the determined status of the one ormore channels; supporting communications with one or more other wirelesscommunication devices using the at least one channel during one or moretimes based on the determined status of the one or more channels;receiving a packet via a first two or more channels within thepredetermined frequency band or a second two or more channels within thepredetermined frequency; processing the packet to determine the statusof the first two or more channels using a first CCA level when thepacket is received via the first two or more channels; and processingthe packet to determine the status of the second two or more channelsusing a second CCA level when the packet is received via the second twoor more channels.
 15. The method of claim 14 further comprising:processing the one or more packets to determine a rate at which the oneor more packets is received; and selecting the one or more CCA levelsbased on the number of channels of the one or more channels, the one ormore bandwidths of the one or more channels, and the rate at which theone or more packets is received.
 16. The method of claim 14 furthercomprising: receiving the packet via a first channel within thepredetermined frequency band or a second channel within thepredetermined frequency band; processing the packet to determine thestatus of the first channel using a first CCA level when the packet isreceived via the first channel; and processing the packet to determinethe status of the second channel using a second CCA level when thepacket is received via the second channel.
 17. The method of claim 16,wherein: the first channel is located within a first frequency sub-bandof the predetermined frequency band; and the second channel is locatedwithin a second frequency sub-band of the predetermined frequency bandthat is wider or narrower than the first frequency sub-band.
 18. Themethod of claim 14 further comprising: supporting the communicationswith the one or more other wireless communication devices using a firstchannel at or during a first time; and supporting the communicationswith the one or more other wireless communication devices using a secondchannel at or during a second time.
 19. The method of claim 14, wherein:the first two or more channels are located within a first frequencysub-band of the predetermined frequency band; and the second two or morechannels are located within a second frequency sub-band of thepredetermined frequency band that is wider or narrower than the firstfrequency sub-band.
 20. The method of claim 14, wherein the wirelesscommunication device is a wireless station (STA) or a smart meterstation (SMSTA), and the one or more other wireless communicationdevices includes another STA, another SMSTA, or an access point (AP).